Facebook's new Graph Search, in limited beta release, extends searches for singles on the network to friends of friends. The new feature, primarily for finding what friends "Like" from music to food and more, is expected to be available more widely over the next few months.

After years of playing a de facto cupid among friends, Facebook is no longer just dipping a toe in the online-dating hot tub. "For dating queries, friends of friends tends to be a good place to start," says Tom Stocky, Facebook director of product management.

Graph Search, a promising advertising bonanza and Google threat, puts people's interests and relationship status only a fingertip away. It offers a speedy way to sort potential mates. Men will be able to hunt for single women who live in their locale and like a particular taco stand, action movies such asThe Expendables, and sports teams, for example. Women could search for single men who like the movieBridget Jones's Diary, a book about knitting and old episodes ofFriends.

Graph Search, paired with Facebook's Messenger and Poke apps, will now provide what amounts to a basket of dating tools. Messenger is a way to see people who are online in order to strike up a chat. Poke allows people to send flirtatious messages or photos that expire within a short set time period.

"Without a doubt men will be taking advantage of this and without a doubt women with attractive profile photos will be harassed and irritated," said Neil Strauss, author ofThe New York Timesbest sellerThe Game, a book about the pickup artist culture. "Single, desperate men are among the first to exploit any new technology that will help them in their quest."

For Facebook, a more direct move into courting rituals could fuel member growth and position the company to attract advertising related to those singles searches. Flower delivery, candy stores and restaurant ads might come into play.

And with a greater focus on dating, companies such as Match.com and eHarmony could have a new hulking, free rival knocking. Match.com and eHarmony did not respond to requests for comment.

At stake is a U.S. dating market that represented more than $2.1 billion in business for 2012, according to MarketResearch.com.

Discovering Mr. Right

Facebook's Graph Search will help people better reconnect with that special someone they met at a party but only recall a first name and a few other details, the company says.

Nate Elliott, a Forrester analyst who covers Facebook and social marketing, cautions against using Facebook as a dating destination.

"It's a different use case than the online dating sites. When someone is on an online dating site you can be pretty sure they are looking for a date. When somebody list themselves as single on a social network you can't be so sure."

Dating norms, however, have already taken root on Facebook. People have long-perused the photos and postings of members in the game of attraction, says Julie Spira, a digital-dating maven who runs CyberDatingExpert.com.

"It's the world's largest social network, and they could be the world's largest dating network if they want to go there," Spira said.

Nowadays it is common to use Facebook as a vetting process to find somebody who knows a person you might date, or to look for red flags - such as "hate romantic comedy movies" - in written postings.

People already use "Facebook as sort of a research tool to see if they have friends in common, to talk with that person to see if they will vouch for them," said Spira. It is common for new singles back on the dating scene to strike up chats on Facebook Messenger to make a match, she said.

Facebook pestering?

Author Strauss cautions that Facebook's dating tools may create annoyances on the site. Women may get too many unwanted advances and notes from men they aren't interested in.

That could lead to an influx of Casanova e-mails and recipients ultimately clamping down to make profiles more private, he said.

"With MySpace, one of the reasons people left is their in-boxes got spammed," Strauss said.

Disturbances are always a risk, experts says, but people can't get too out of line because their identity is known and they can ultimately be "unfriended" at the click of a mouse.

"Facebook's very public personage may prohibit people from behaving inappropriately. There are behavioral limits on Facebook from the get-go," said Mark Cooper, CMO and co-founder of Offerpop, which helps marketers run campaigns on Twitter, Facebook and Pinterest.

Facebook says it's keenly aware about privacy concerns with Graph Search, and intends to make it clear to its members that what they share and tag in photos could be publicly viewable.

The Search Graph, for now, only culls "Like" selections and has yet to tap into profiles or News Feed data.

Graph Search launch

From online dating and beyond, Facebook's foray into search, announced on Tuesday, could have far-reaching implications for competitors, advertisers and consumers.

Such a plethora of data could have big appeal to advertisers and marketers who want to target their ads on Facebook. And it is a potential broadside to Google, Yelp and Foursquare. Even LinkedIn faces competition: Graph Search is a good way, as Facebook demonstrated, to job recruit.

Facebook CEO Mark Zuckerberg insists the new feature is not Web search. But as Graph Search develops, it may more closely resemble Google.com, assuming Google integrates Google+ into its search service.

Facebook raked in about $4.2 billion from advertising last year - 84% of its estimated $5 billion in total revenue, according to eMarketer.

Still, cautions Forrester's Elliott: "Even if they figure out how to grab all this data and plug it into the ad platform, they still haven't been able to offer it to marketers in a meaningful manner."